Doxygenification

There is apparently somebody out there bored enough to publish our Doxygenized code for the entire world to see. This makes it that much more important that we update and clean up our Doxygen-targeted internal comment documentation.

Please have a look at the existing Doxygen-based docs, and then look at the doxygen style info page for help figuring out how to clean up the existing mess, and extend it into something vastly more useful going forward.

(More suggestions/guidelines may appear as Michael gains more experience twiddling all of this.)